Railroad car with elastic means to isolate van size container thereon



Aug. 30, 1966 G. A. SCHMIDT 3,269,333

RAILROAD CAR WITH ELASTIC MEANS TO ISOLATE VAN SIZE CONTAINER THEREON 5 Sheets-Sheet 1 Filed Nov. 25, 1964 m m m r m/:

u w um (1L m 4 w 6 w W e m GEORGE A. SCHMIDT BY ATTORNEYS Aug. 30, 1966 G. A. SCHMIDT RAILROAD CAR WITH ELASTIC MEANS TO ISOLATE VAN SIZE CONTAINER THEREON Filed Nov. 25, 1964 r il) 5 Sheets-Sheet 2 INVENTOR.

GEORGE A. SCHMIDT MMJW ATTOR NEYS A. SCHMIDT RAILROAD CAR WITH ELASTIC MEANS TO ISOLATE' VAN SIZE CONTAINER THEREON 3 Sheets-Sheet 3 Filed Nov. 25, 1964 ATTORNEYS United States Patent 3,269,333 RAILROAD CAR WITH ELASTIC MEANS TO ISO- LATE VAN SIZE CONTAINER THEREON George A. Schmidt, Langhorne, Pa, assignor to Strlck Corporation, Fairless Hills, Pa, a corporation of Pennsylvania Filed Nov. 25, 1964, Ser. No. 413,779 Claims. (Cl. 105--366) This invention relates to a railroad car for use in containerized cargo wherein freight-laden van size containers or cargo bodies are transferred to the car from over-the-road wheel assemblies, a flat truck, a loading platform or a ship.

It has been found that when a trailer body rides upon a railroad flat car lateral racking of the rear of the body is produced causing the frames to fail at the corners, putting severe strain on the rear door hinges and subjecting the hardware components to extreme wear. The racking results from jars transmitted from the railroad car truck as it passes over the alternating joints of the rail or track sections. At first it was felt that this racking is caused only by lateral motion of the deck of the railroad car. However, after continued observation and study of the phenomenon, it is now believed that this racking is caused by a rolling action generated by the fact that when the truck wheels drop to a lower level at a rail joint, the railroad car pivots about a stable point on the opposite rail, then the car recovers after passing that joint and the rolling action is repeated as the car passes an alternating joint on the opposite rail. At normal operating speeds, the oscillating frequency generated is approximately two to three cycles per second.

The primary object of the invention is to provide elastic isolators between the trailer body and the deck of the railroad car whose elastic centers are so oriented as to enable the car to roll without displacing the trailer body, thereby reducing the racking of the rear of the trailer body to a minimum.

Another object of the invention is to provide elastic isolators of the character described which are symmetrically mounted relative to a vertical plane defining the longitudinal center of the railroad car and so oriented that the elastic axis of the system falls below the deck of the railroad car and on the longitudinal center of the car so that the rolling action, due primarily to alternating vertical and lateral forces generated as indicated hereinbefore, is not transmitted in significant magnitude to the trailer body.

Another object of the invention is to provide elastic isolators between a trailer body and the deck of a railroad car wherein the lines from the geometrical centers of the symmetrically mounted isolators if passed through the aforesaid elastic axis intersect or approach very closely to the rails so that couples or moments originating at the rails will cause the truck and the railroad car, but not the trailer body, to rotate about the elastic axis of the system.

These and other objects of the invention will become more apparent as the following description proceeds in conjunction with the accompanying drawings, wherein:

FIG. 1 is a fragmentary side elev-ational view of a railroad car showing elastic isolators between the rear portion of a trailer body and the railroad car;

FIG. 2 is a view similar to FIG. 1 showing elastic isolators between the front and rear portions of a trailer body and the railroad car;

FIG. 3 is a rear elevational view, some parts being shown in section, of the railroad car and trailer body mounted thereon;

FIG. 4 is a top plan view of an end portion of the 3,269,333 Patented August 30, 1966 railroad car, some parts being broken away and omitted for purposes of clarity;

FIG. 5 is an enlarged sectional view of one of the elastic isolators taken on the line 5-5 of FIG. 4; and

FIG. 6 is a view similar to FIG. 5 illustrating a modified form of the invention.

Specific reference is now made to the drawings in which similar reference characters are used for corresponding elements throughout.

Indicated generally at 10 is a railroad flatcar which is conventional except for modifications which may be required therein for the mounting for the elastic isolators as will appear hereinafter. The form of railroad car shown comprises a center si-ll 12, cross bolsters 14 secured to and extending laterally from the center sill, side sills 16 secured to the ends of the cross bolsters and a deck plate 18 secured upon the center sill. The railroad car includes conventional trucks 20 comprising, among other things, a frame 22 mounted to the center sill and flanged wheels 24 engaging tracks or rails 26.

The elastic members to isolate a van size trailer body 28 from the deck of the railroad car are generally shown at 30 and may be afiixed to the car deck and interposed between the rear end of the car and rear portions of the trailer body, in which case the kingpin 32 at the front of the body will be latched into a receiver 34 on the rai road car, are shown in FIG. 1, or the elastic isolator members may be interposed between the front as well as the rear portions of the trailer body and the railroad car, as shown in FIG. 2. It will also be understood that the elastic isolators may be affixed upon the side sills 16 or the cross bolsters 14 or combinations thereof.

In some applications of containerized cargo, it is advisable to provide track angles 36 which are secured to the bottom of the trailer body along its sides and adjacent its rear end, the vertical flange 38 of the track angle being apertured as at 40 to permit coupling to an over-the-road wheeled unit and when uncoupled therefrom, the trailer body can be slid off the wheeled unit or lifted therefrom onto a ship, loading platform, railroad car, etc. When such a container or trailer body is mounted on the railroad car, the deck of the car is altered to permit mounting of the elastic members in such a manner as to simplify support of the container on the car over the elastic members.

Thus troughs 42 substantially of hat-shaped cross section are provided, each being secured as by welding or other suitable means to the longitudinal edge of the deck 18 and the corresponding side sill 16, as seen in FIG. 3, the troughs being at least as long as the elastic units 30. Spaced substantially triangular transverse .gusset plates 44 are welded in the trough 42, extend above the deck and are in turn welded to a further inner longitudinal plate 46 which is also welded at its lower edge in the trough. As seen clearly in FIG. 3, the plates 46 are spaced equidistantly from the longitudinal center of the car and extend at an inward angle of about to the horizontal or plane of the deck. Thus the plates converge upwardly and diverge downwardly of the deck.

Each elastic member 30 is of the sandwich type comprising substantially rectangular solid natural rubber blocks 48 with substantially coextensive metallic plates 50 bonded between adjacent faces of the blocks forming a laminate which increases the compressive strength thereof. In cross section the member 30 is of step construction, and is preferably 4%" high, 5% at its widest and 14%" at its longest and has a shear rate of about 3,000 lbs/in. of shear deflection and a compression rate twenty times that of the shear rate or 60,000 lbs/in. of compression deflection. The plate 50 of the innermost block carries bolts which extend through the plate 46 and are secured thereto by appropriate nuts 52.

Another outer longitudinal plate 54 is provided which is coextensive with and parallel to the inner plate 46 except for an outer end portion 56 which is in the form of a horizontal ledge. The plate 50 of the outermost block 48 carries bolts which extend through the outer plate 54 and there secured by appropriate nuts 58. Secured as by welding upon the outer plate 54 is an upper frame member in the form of an angle plate 60 which is complementary to the track angle 36 of the container. Thus the plate 60 has a horizontal portion 62 which is welded to the outer plate 54 and a vertical portion 64 which is welded to the ledge 56 and reinforced by a substantially rectangular bar 66, see FIGS. and 6. Thus when the trailer body is supported on the railcar, the horizontal portion of the body track angle 36 rests on the horizontal portion 62 of the upper frame member 60 and the vertical portion 38 of the track angle 36 abuts the vertical portion 64 of the upper frame member 60, as seen in FIG. 3. The engagement of the vertical portions 38 and 64 serves to limit relative lateral movement between the trailer body and the railroad car. Relative longitudinal movement can be limited by other means not here shown. Where loading upon the railcar is effected by a crane, the track angle 36 can be eliminated from the trailer body and instead holes 66 can be provided in the bottom of the trailer body to receive tapered pins 68 upstanding from the horizontal leg 62 of the upper frame member 60, as shown in FIG. 6, the pins 68 serving to limit lateral and longitudinal movement of the trailer body relative to the railroad car.

The elastomeric members 30 are tied together by further cross members or angle bars 7 0 which are terminally welded to the outer or upper plates 54. As a result of the fact that the elastomeric members 30 are symmetrically mounted relative to the vertical plane, see FIG. 3, defining the longitudinal center 72 of the railroad car, the elastic axis 74 of the system, including the railroad car (the rigid body) and the elastomeric members, falls below the deck of the railroad car and along the vertical plane defining the longitudinal center 72. By definition, the elastic axis is a line whereby if a constant force is applied to the rigid body along a line extending through said axis, the body is displaced in translation without rotation, and if a constant moment is applied with respect to the elastic axis the body is displaced in rotation without translation. Because the elastic axis 74 falls below the deck of the railroad car the rolling action of the truck and railroad car as the wheels pass over alternating rail joints is not transmitted in significant magnitude to the trailer body.

It will also be seen from FIG. 3 that because the elastomeric members are positioned each at an acute angle to the plane' of the deck and so oriented that the angle is inward of the railroad car, the lines 76 from the geometrical centers of the blocks through the elastic axis 74 intersect the rails 26 or come very close to them so that couples originating at the rails will cause the railroad car and truck, and not the container, to rotate about the clastic axis 74.

While a preferred embodiment of the invention has here been shown and described, it will be understood that skilled artisans may make minor variations without departing from the spirit of the invention and the scope of the appended claims.

I claim:

1. In combination with a container, a railroad car including a deck means, inner transversely spaced, longitudinal, vertically extending bars each secured at acute angles to said deck means and converging upwardly, outer transversely spaced longitudinal members including walls spaced from and substantially parallel to said bars, a rigid member extending transversely between and connecting said outer members, said outer members supporting said container, and elastomeric members secured between said bars and said walls and having shear axes, when relaxed, which are substantially parallel to said bars and walls, the elastic axis of the system falling below said deck means and on a vertical plane defining the longitudinal center of said railroad car, said elastomeric members acting to substantially reduce transmission to said container of the repeated vertical and lateral forces to which the railroad car is subjected as it rolls over alternating joints of rail sections to thereby prevent back and forth racking of said container which racking puts severe strain on said container causing undue wear and at times corner failure.

2. The combination of claim 1 wherein said railroad car includes a truck and wheels having rail-engaging surfaces, the lines from the geometrical centers of said elastomeric members through the elastic axis falling adjacent said rail-engaging surfaces of said wheels.

3. The combination of claim 1 wherein each elastomeric member is a laminate of rubber blocks with metallic plates bonded between adjacent faces of said blocks.

4. The combination of claim 1 wherein said deck means includes longitudinal trough members on both sides of said longitudinal center of said railroad car and extending beneath the plane of said deck means, said inner bars being secured in said trough members.

5. The combination of claim 1 and means on said outer members engageable with said container to limit lateral and longitudinal movement of said container relative to said railroad car.

References Cited by the Examiner UNITED STATES PATENTS 2,071,355 2/1937 Norbom -366 2,728,309 12/1955 Candlin 105-454 2,782,026 2/1957 Hirst 105-197 2,954,747 10/1960 Hirst et al 105-196 3,112,040 11/1963 Levitt et al. 214-38 3,144,838 8/1964 Shaver et al. 105-366 3,160,117 12/1964 Willison et al. 105-366 3,161,150 12/1964 Sable 105-366 3,168,876 2/1965 Clejan 105368 3,179,067 4/1965 Beck et al 105-368 OTHER REFERENCES Flexi-Van Piggyback Car Mark III, Railway Age, Dec. 4, 1961, page 17 relied upon.

ARTHUR L. LA POINT, Primary Examiner.

D. E. HOFFMAN, Assistant Examiner, 

1. IN COMBINATION WITH A CONTAINER, A RAILROAD CAR INCLUDING A DECK MEANS INNER TRANSVERSELY SPACED, LONGITUDINAL, VERTICALLY EXTENDING BARS EACH SECURED AT ACUTE ANGLES TO SAID DECK MEANS AND CONVERGING UPWARDLY, OUTER TRANSVERSELY SPACED LONGITUDINAL MEMBERS INCLUDING WALLS SPACED FROM SAID SUBSTANTIALLY PARALLEL TO SAID BARS, A RIGID MEMBER EXTENDING TRANSVERSELY BETWEEN AND CONNECTING SAID OUTER MEMBERS, SAID OUTER MEMBERS SUPPORTING SAID CONTAINER, AND ELASTOMERIC MEMBERS SECURED BETWEEN SAID BARS AND SAID WALLS AND HAVING SHEAR AXES, WHEN RELAXED, WHICH ARE SUBSTANTIALLY PARALLEL TO SAID BARS AND WALLS, THE ELASTIC AXIS OF THE SYSTEM FALLING BELOW SAID DECK MEANS AND ON A VERTICAL PLANE DEFINING THE LONGITUDINAL CENTER OF SAID RAILROAD CAR, SAID ELASTOMERIC MEMBERS ACTING TO SUBSTANTIALLY REDUCE TRANSMISSION TO SAID CONTAINER OF THE REPEATED VERTICAL AND LATERAL FORCES TO WHICH THE RAILROAD CAR IS SUBJECTED AS IT ROLLS OVER ALTERNATING JOINTS OF RAIL SECTIONS TO THEREBY PREVENT BACK AND FORTH RACKING OF SAID CONTAINER WHICH RACKING PUTS SEVERE STRAIN ON SAID CONTAINER CAUSING UNDUE WEAR AND AT TIMES CORNER FAILURE. 